Gynecology and Reproductive Endocrinology

Exercise during pregnancy activates cardio-protective genes without a
further increase in pregnancy-induced cardiac hypertrophy.

Exercise and pregnancy are known to induce physiological cardiac hypertrophy, and the molecular mechanisms have recently been revealed exercise-induced and pregnancy-induced cardiac hypertrophy. However, current understanding of the interaction of exercise and pregnancy on heart health is poorly understood. Our objectives were to study how exercise during pregnancy modifies pregnancy-induced cardiac hypertrophy and to determine gene expression patterns when two different physiological hypertrophic stimuli are concurrent. Female C57BL/6 mice were divided into three groups: non-pregnant sedentary control (C), sedentary pregnant (LP), and exercise during pregnant (ExP) groups. The mice in the ExP group were exercised voluntarily from gestational day 1 through gestational day 17, at which time they were sacrificed. Both the ExP and LP groups showed a significant increase in heart mass compared to the C group. Phosphorylation of Akt, mTOR, and p70S6K were all significantly increased in the hearts of the ExP group when compared to the C group. Phosphorylation of mTOR was different between the ExP and the LP groups. The ExP group displayed significant upregulation of α-myosin heavy chain compared to the LP group. In addition, the ExP group significantly downregulated Ccl2 (monocyte chemotactic protein) compared to the C group. Taken together, our results demonstrate that exercise during pregnancy initiated at day one of gestation may be beneficial by activating several cardiac protective genes.